The present invention relates to a construction along a double curved surface. Such constructions are generally known, for instance as a spherical skin-shaped construction or as a construction with the form of a hyperbolic paraboloid.
With known techniques it is not possible to continuously clad double curved surfaces with the same plates. Use is then usually made of plate-like elements partially overlapping each other. These elements result in material loss, they require much labour in fitting and lead to sealing problems in respect of water drainage.
A preferred embodiment of the present invention undertakes to avoid these drawbacks. This secondary objective is achieved by a supporting construction which is formed by:
supporting elements extending substantially parallel, the supporting sides of which are situated within the double curved surface; and PA1 strips of substantially planar, slightly flexible material, the width of which is at least equal to the distance between elements, which strips extend between adjacent elements. PA1 a number of regularly distributed primary main elements extending radially along the construction from the centre to the edge; PA1 a number of secondary main elements corresponding with the number of primary main elements and extending radially intermediate the main elements; PA1 primary sub-elements extending parallel to the closest primary main element from the secondary main elements to the edge such that the distance between the primary main element and the closest primary dub-element and the mutual distances between the primary sub-elements are substantially equal; PA1 strips of substantially flat, slightly flexible material which extend to the edge from each secondary main element between a pair of primary sub-elements, respectively between a primary sub-element and a primary main element, wherein the strips are supported by the primary sub-elements, respectively by a primary sub-element and a primary main element and the width of which is at least equal to the mutual distance between the primary sub-elements.
The above stated drawbacks are avoided as a result of these steps.
The present invention relates particularly to a spherical skin-shaped construction.
Such constructions are generally known. Common use is herein made of for instance triangular or hexagonal elements which are either self-supporting and joined together to form an entity or are placed in a pre-constructed frame so that a closed spherical skin-shaped structure is obtained.
The problem in these known constructions is that it is not possible to clad a spherical skin-shaped structure with one type of element, for instance a triangular element. A planar surface will in any case result from joining together triangles. Six triangles herein converge at one angular point.
When five triangles converge at one angular point this results in a regular icosahedron. Four triangles converging in an angular point result in a regular octahedron; and three triangles converging in a triangular point result in a regular tetrahedron.
Also when cladding takes place with regular hexagons a planar surface will result.
It is thus not possible to cover an approximately spherical skin-shaped surface with regularly formed geometric elements. In order to cover a spherical surface it is therefore necessary to have available a number of elements whereof the dimensions are unequal. Experience has taught that a large number of different elements must be used to build such a spherical skin-shaped structure. This naturally has the effect of increasing the cost of such a structure.
This applies both in the case of a self-supporting construction and a construction wherein cladding elements are fixed to a frame.
A secondary objective of the present invention is to provide a substantially spherical skin-shaped construction which can be built at a comparatively low price.
This object is achieved by a substantially spherical skin-shaped construction as according to claim 1 comprising:
As a result of these steps only primary main elements, secondary main elements and primary sub-elements need be kept in stock in addition to rolls of cladding material.
As a consequence hereof the total number of different components required for the construction is considerably limited, while the primary main and sub-elements can correspond with one another. Further, the strips of cladding material are simply material supplied to length which can be shortened so that it can be delivered on rolls. Use of folded or corrugated plate results in a still greater cost limitation.
The secondary sub-elements used in accordance with a preferred embodiment also have only a small cost-increasing effect; however, they make a considerable contribution towards the construction strength.
According to an embodiment the elements are formed by rods mutually connected in joints. The elements could be formed by girders or walls. It is also possible to apply a grid construction in the form of a continuous skin.
The present invention thus provides a spherical skin-shaped construction the building costs of which are considerably reduced compared to the currently known art for building such structures.